# Phenotypic Features in a New 12q21 Deletion and Its Association With Cardiofaciocutaneous Syndrome

## TL;DR

This paper reports a rare chromosomal deletion in the 12q21 region and suggests it may be linked to Cardiofaciocutaneous syndrome.

## Contribution

The paper presents a novel case of a de novo 12q21 deletion not previously reported and proposes its association with CFC syndrome.

## Key findings

- The deletion in the 12q21 region is associated with cardiac, renal, ocular, CNS, and developmental abnormalities.
- The case suggests a possible new microdeletion syndrome linked to the 12q21 deletion.
- This is one of the few reported cases of interstitial deletions in the long arm of chromosome 12.

## Abstract

Arriving at a diagnosis in children with developmental delay, cognitive impairments, and multiple physical abnormalities at birth can be very taxing due to many differential diagnoses and etiologies. Of the plethora of conditions that are seen among infants, chromosomal disorders, in particular, present with challenges in diagnosis and devastating consequences. In recent times, the advent of chromosomal microarray techniques has made it possible to easily identify chromosomal deletions and arrive at a diagnosis. This case comprises one of the very few cases reported in interstitial deletions of the long arm of chromosome 12. To date, only 14 patients with deletions, including the 12q21 region, have been reported. The main features are cardiac, renal, ocular, CNS, and developmental abnormalities. The shared features of all these cases might suggest a possible microdeletion syndrome. In this case report, we propose through descriptive analysis that a deletion of genes in the 12q21 region could lead to CFC syndrome. This work contributes to our understanding of the 12q21 deletion syndrome through the case discussion of a one-year-seven-month-old boy with a de novo deletion at 12q21.1q21.31 region that has never been reported previously.